Monday, April 9, 2012

The Rule-Based Dungeon

I have more to do with modular dungeons and stencils but I want to take a little detour to think about what a dungeon location that changes based on certain rules might look like.  This seems risky because a) the rules might be hard for players to discover, and b) it might be really frustrating.  Let's see what we come up with anyway.

Okay, imagine a dungeon with set dimensions, maybe a page of graph paper or so that changes depending on the answer to certain logic statements.  Now we aren't randomly generating a dungeon here; if you make sure the same statements are triggered the dungeon should be exactly the same each time.  What do I mean?  How about, If a cleric is in the party then the Altar room will appear.  Or, if there are more than 2 in a party the stairs to the second level appear.

Who would build such a place?  I'm not sure, it might depend on what rules you set.  In some ways it seems very chaotic-- the shape of the dungeon shifting constantly-- but in others it is the definition of Law-- when these strictures are met the dungeon will always be a certain layout.

This reminds me of Vows, and those could be the rules that are involved, for example if no blood is shed in the dungeon then a fountain will appear.  But it also reminds me of fairy tales: On nights of a full moon there is a city in the bottom of the lake.  Actually the fairy tale route might be a good way to go because by telling players some of these rules ahead of time you might avoid our problems a and b above.  And that would make it more vow-like, because players would know what the rules were and hopefully they would be challenging or amusing rules to try and not break.  Hmm, yeah not very different from that oaths and vows post after all.  But what about coming from the other direction?  What dungeon features might be interesting to pop in and out of existence.
  • Access.  In one example above I used stairs.  Doors, bridges, hatches, ladders, stairways to heaven, haha.
  • Resource areas: altars, fountains, mushroom fields,
  • Geological features: geysers, waterfalls, springs, rivers, pools, stalactites/mites
Hmm, this is seeming more local than I first imagined, but sort of like the invisible dungeon maybe this would be better in small doses.  It makes sense, that if rule knowledge is a potential problem for players you would want to limit the number of rules.  So instead of a whole dungeon that shifts around because of a variety of rules you have a relatively normal dungeon with a very special feature affected by some fairy tale like rule-- "the seven pools will only appear on moonlit nights when a virgin is near."

But maybe we're shutting down possibilities too early, let's backtrack and think of more, non-vow-like things that could trigger dungeon statements:
  • I mentioned party #, party make-up, level, gender/age mixture, cultural/ethnic (only a true Women of the West will see the door)
  • party gear- if they have magic items, familiars, relics
  • time of year, season, weather, day/night, moon cycle
  • Whether party uses light, is noisy, camps, eats/drinks in the dungeon
  • Multiple visits-- whoa, that's a whole new idea-- the dungeon that shifts somehow with each visit
Now I'm reminded of the idea of "your true heart's desire" from fantasy.  A warrior sees a glorious battle, a mage is met with a vast library.   I could be very dream-like or heaven-like, in that it shifts based on who is there to experience it.  I especially like that idea for a solo adventure.  Imagine a hard to reach tower that players can quest to/enter when they are the only ones to show up on game night, but what is in it differs depending on who it is.  This might be strictly based on class or alignment tendencies, but if you wanted to get a little fancier, you could shape it to what you know about your player-- If Jane like puzzles and everyone else in the group hates them, it's a puzzle tower.  If Bob likes combat, he's like Bruce Lee in the Tower of Death.

What about contexts outside the gameworld itself?  This would be harder to trigger with busy schedules and such, but you might have a dungeon that only has certain features if you go there on the real Halloween.  Or, visit the dungeon on your birthday and the birthday fountain is there, or hah, the Flagon Wagon, travelling brew pub and eatery.  But now I'm drifting more into events than structures (like Santa Claus showing up in Narnia).

Back to how the dungeon might change.  I realize I focused above on what could be true or not, but what about continuums?  These also might change in the dungeon based on certain rules:
  • ceiling height
  • light level
  • temperature
  • water depth
  • room dimensions
  • creature population densities
  • wind intensity
  • sound/smell
Anyway, what do you think?  Have you shifted a dungeon on rules before?  What shifts might interest you as a player?


  1. I can't remember were I got this, but I've used doors that only open or only appear in certain predefined circumstances. The key is that the rule must be discoverable by the players, or else if might as well be random. When I use such doors, the players learn the rules from a rumor or treasure map, or the site/room suggested the rule by its physical configuration or decorative motif.

    The real-world condition reminds me of Animal Crossing.

    1. That's how you open gates in Planescape.

      By the way, the whole idea is extremely cool. You could have trees of conditions, with necessary conditions to be fulfilled to trigger more behaviours: for example, if a paladin enters the dungeon, a devil appears. If the devil kills a paladin's companion, a pie will appear. If the orc ates the pie, blah blah blah. Arrange the graph as desired, solve per x.

  2. I'm a little surprised that the idea of recurring visits to the same such dungeon didn't occur until midway through the post; that seemed to be the most immediately suggested thing to me. And this would be a spectacular way to model the old "mythical underworld" megadungeon; this place runs on rules... but they're crazy, arbitrary rules that you, the players, will have to gradually figure out. Until then, it's a madhouse.

    Some of the real-world-event correlated ones seem a bit gamey to me, but overall I think this is a great idea, and may have to give it a shot.

  3. I think this sounds a lot of fun. I'd hope it wouldn't frustrate a lot of people but if it's more of an extra perhaps it won't be too bad

  4. Pokemon uses a bunch of real world clock events - this critter only appears for one week at the end of spring or the bug hunt only runs between 2 and 6 o clock on Fridays. Could actually be REALLY interesting for a flailsnails game. Creates anticipation and maybe emergent co-operation. What if you need to leave a character holding the dimensional portal open to get access to the World of High Quality Firearms. You can leave them with a companion, food and water, but you'd still better come back for the next session of play within 48 hours and with caffeine pills.

    Otherwise, I'd say definitely reveal some fairytale rules at the start - lets you guide the players as to what sorts of rules there could be (because this is the epitome of "guess what I'm thinking" puzzlemaking). The invisible maze... you can only see with a Hand of Glory? Is visible only to goblins/ghosts/githyanki? Must be walked in exactly the right pattern regardless of incoming missile fire? I can see a lot of painful fun here.

  5. Personally I really enjoy access restrictions over magically triggered, or randomly (and orderly) shifting rooms.

    A limestone cave complex can totally change with water, and it can change differently over different scales of time since sumps and rooms could fill/empty with water at different paces. A particular hallway could be passable every hour, or once a week depending on the flows, and even with water breathing, cave diving is one of the most dangerous hobbies ever (and that's without monsters).

    Ruins in the sand is another way to go, especially if there are large cavernous places far beneath the surface to which that sand can flow.

    My favorite though would have to be ice caves, or ruins beneath a glacier (as I imagine Lovecraft's Antarctic city). Ice caves constantly change due to wind, water, and thermal vents, so every time you enter them it's acceptable for them to be dramatically different. You can use geomorphs to draw up multiple ice cave maps which you can then place on top of your ruins map to see which parts of the ruin are accessible this trip vs the previous trip. No magic required!

  6. Thanks for the great comments, all. I think there is more meat to talk about here, but I haven't sorted it yet. Started a Venn diagram this morning, will think more about it.

    @Pandesmos, I dig the idea of the ice caves overlaid over a base map. I proposed something sort of similar with cave ins altering a base map here:

    I was also thinking of a dungeon produced by the digging of sandworms, it's temporary-- old tunnels collapse-- but evergreen-- the worms dig new tunnels.

  7. You could also use these as a reference:

  8. Thanks, Kadmon. I hadn't seen those. Though, the more I think about it the more time-based rules seem like they would require an unattractive amount of bookkeeping on the part of the DM.